Method, system and storage medium for controlling exhaust gases produced by an internal combustion engine

ABSTRACT

A method for controlling exhaust gases produced by an internal combustion engine, a medium encoded with a machine-readable computer program code for controlling exhaust gases produced by an internal combustion engine and a system for controlling exhaust gases produced by an internal combustion engine is provided wherein the system includes a vehicle sensor and an engine control module and wherein the method includes obtaining a vehicle data signal responsive to the engine performance of the internal combustion engine, processing the vehicle data signal so as to formulate an engine operating parameter, wherein the engine operating parameter is responsive to the hydrocarbon content of the exhaust gases and controlling the fuel introduced into the internal combustion engine in a manner responsive to the engine operating parameter.

BACKGROUND

[0001] Internal combustion engines produce large quantities of exhaust gases consisting primarily of carbon dioxide (CO₂), water, unburned hydrocarbons (HCs), carbon monoxide (CO), and oxides of nitrogen (NO_(x)). 1 However, since the 1970's the emission of unburned HCs, CO, and NO_(x) have been strictly regulated and regulatory requirements seeking to reduce these exhaust gas emissions have become increasingly stringent and hence more difficult to meet. For example, the Clean Air Act Amendment of 1990 mandates that emission generating industrial plants develop and/or implement techniques to significantly reduce their emissions of NO_(x). Such legislation affects a wide variety of industry that employ internal combustion engines such as power plants, iron and steel plants, pulp and paper mills, acid production plants, petroleum refineries, lime plants, fuel conversion plants, glass fiber processing plants, charcoal production plants, cement plants, copper smelters, coal cleaning plants, etc.

[0002] As a result, many present day internal combustion engines, such as the gasoline-fueled engines used for passenger automobiles and the like, operate very near stoichiometric conditions, where the catalyst technology that allows simultaneous abatement of unburned HCs, CO, and NO_(x), is rather well advanced. In addition, because of significant fuel economy advantages and attendant lower fuel costs, there is a desire to introduce compression ignition engines, such as diesel and gasoline lean-burn vehicles on a broader basis. Because these vehicles operate with an air to fuel ratio that is above the stoichiometric ratio, such that the resulting exhaust gases are “lean”, they have relatively high concentrations of oxygen and relatively low concentrations of HC's, CO's, and/or hydrogen (H). However, because these compression ignition engines are not able to adequately abate the NO_(x) component of the pollutants in the exhaust stream, they still emit a relatively high concentration of NO_(x).

BRIEF SUMMARY

[0003] A method for controlling exhaust gases produced by an internal combustion engine comprises: obtaining a vehicle data signal responsive to the engine performance of the internal combustion engine; processing the vehicle data signal so as to formulate an engine operating parameter, wherein the engine operating parameter is responsive to the hydrocarbon content of the exhaust gases; and controlling the fuel introduced into the internal combustion engine in a manner responsive to the engine operating parameter.

[0004] A system for controlling exhaust gases produced by an internal combustion engine comprises a vehicle sensor for obtaining a vehicle data signal responsive to the engine performance of the internal combustion engine; and an engine control module for processing the vehicle data signal so as to formulate an engine operating parameter, wherein the engine operating parameter is responsive to the hydrocarbon content of the exhaust gases, and wherein the engine control module controls the fuel introduced into the internal combustion engine in a manner responsive to the engine operating parameter.

[0005] Also claimed is a medium encoded with a machine-readable computer program code for controlling exhaust gases produced by an internal combustion engine, the medium including instructions for causing controller to implement the aforementioned method.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Referring now to the drawings, wherein like elements are numbered alike in the several figures in which:

[0007]FIG. 1 shows a block diagram describing an overall method for controlling exhaust gases produced by an internal combustion engine in accordance with an exemplary embodiment; and

[0008]FIG. 2 shows a schematic diagram of a vehicle having an internal combustion engine which incorporates a non-thernal plasma reactor in accordance with an exemplary embodiment.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT

[0009] One way to reduce the emission of NO_(x) components is to introduce HC's after compression ignition has occurred. The resulting exhaust gas is then applied to oxidizing equipment, such as a non-thermal plasma reactor, where the NO_(x) emissions are oxidized into NO₂ and HC's are partially oxidized into aldehydes, keytones, and alcohols. The resulting NO₂ and partially oxidized HC's are adsorbed and reacted on a catalyst bed. The partially oxidized HC's reduce the NO₂ to N₂. However, in order for the aforementioned method of reducing NO_(x) components in exhaust gases to perform efficiently, the introduction of HC's into the post compression ignition process must be performed in a controlled manner that is adaptable to varying engine conditions. One way this can be done is by controlling the amount of fuel introduced into an internal combustion engine in a manner responsive to vehicle operating conditions.

[0010] An exemplary embodiment is described herein by way of illustration as may be applied to a device having an internal combustion engine and more specifically a vehicle having an internal combustion engine. While an exemplary embodiment is shown and described hereinbelow, it will be appreciated by those skilled in the art that the invention is not limited to the embodiment and application described herein, but also to any vehicle or device which employs a combustion engine or any system which employs a combustion engine where a method for controlling exhaust gas is desired, such as a motor vehicle or a generator. Those skilled in the art will appreciate that a variety of potential implementations and configurations are possible within the scope of the disclosed embodiments.

[0011] Referring to the figures, a method for controlling exhaust gases produced by an internal combustion engine is illustrated and discussed. In accordance with an exemplary embodiment, a device or vehicle 1 includes an internal combustion engine 10, a vehicle sensor 12, an engine control module (ECM) 14 communicated with the internal combustion engine 10, a non-thermal plasma reactor (NTP) 16 and an exhaust 18. Exhaust 18 is communicated with NTP 16 and internal combustion engine 10. A vehicle data signal is obtained by ECM 14 from vehicle sensor 12, as in step 2 of FIG. 1.

[0012] In accordance with an exemplary embodiment, the vehicle data signal is preferably responsive to the engine torque of the internal combustion engine 10. However it is considered within the scope of the invention that the vehicle data signal may be a single signal or multiple signals responsive to single and/or multiple vehicle conditions, such as engine speed, the temperature of NTP 16, the amount of NO₂ emitted from the exhaust 18 of internal combustion engine 10, exhaust gas volume, exhaust gas temperature and/or transmission gear position. Also, in accordance with an exemplary embodiment, vehicle sensor 12 may be single or multiple vehicle sensors such as an engine torque sensor, NTP 16 temperature sensor, exhaust gas sensor and/or transmission gear position sensor.

[0013] Once the vehicle data signal is obtained by ECM 14, ECM 14 processes the vehicle data signal so as to formulate an engine operating parameter, as in step 4. In accordance with an exemplary embodiment, the engine operating parameter is preferably responsive to the obtained vehicle data signal and/or the hydrocarbon content of the exhaust gases emitted from internal combustion engine 10. Also, in accordance with an exemplary embodiment, the hydrocarbon content of the exhaust gases may be measured using any suitable measuring device and/or the hydrocarbon content may be estimated based on available engine characteristic and/or performance data. The engine operating parameter is then communicated to the internal combustion engine 10 so as to control the fuel introduced into theinternal combustion engine 10, as in step 6. Although the engine operating parameter preferably includes fuel injection parameters, the engine operating parameter may include any engine operational parameters suitable to the desired end purpose.

[0014] In accordance with an exemplary embodiment, the hydrocarbon content of the exhaust gases produced by internal combustion engine 10 is preferably controlled by introducing fuel into internal combustion engine 10 at a predetermined time, wherein the predetermined time is responsive to the combustion process. In addition, the hydrocarbon content of the exhaust gases produced by internal combustion engine 10 are also preferably controlled by controlling the amount of fuel injected into internal combustion engine 10, such as increasing or decreasing the amount of fuel introduced. However, it is considered within the scope of the invention, that the exhaust gases emitted from internal combustion engine 10 may be controlled by other various means, such as controlling the introduction of a fuel additive into internal combustion engine 10 or by controlling the introduction of a gas into the exhaust stream of internal combustion engine 10.

[0015] In accordance with one embodiment, the exhaust gases produced by internal combustion engine 10 are preferably controlled by controlling the introduction of fuel into internal combustion engine 10, in a manner responsive to the acceleration and/or deceleration of internal combustion engine 10. If internal combustion engine 10 is accelerating, then the amount of fuel introduced is increased. However, if internal combustion engine 10 is decelerating, then the amount of fuel introduced is decreased. Depending on the measured and/or estimated hydrocarbon content of the exhaust gases produced by internal combustion engine 10, the amount of fuel introduced into internal combustion engine 10 may also be maintained at a constant rate. In accordance with an exemplary embodiment, this advantageously allows for the control of the hydrocarbon content of the exhaust gases emitted by internal combustion engine 10.

[0016] In accordance with an exemplary embodiment, the processing of FIG. 1 may be implemented by a controller disposed internal, external, or internally and externally to ECM 14. In addition, processing of FIG. 1 may be implemented through a controller operating in response to a computer program. In order to perform the prescribed functions and desired processing, as well as the computations therefore (e.g., the execution of voltage mode motor control algorithm(s), the control processes prescribed herein, and the like), the controller may include, but not be limited to, a processor(s), computer(s), memory, storage, register(s), timing, interrupt(s), communication interfaces, and input/output signal interfaces, as well as combinations comprising at least one of the foregoing. For example, the controller may include signal input signal filtering to enable accurate sampling and conversion or acquisitions of such signals from communications interfaces.

[0017] While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. 

What is claimed is:
 1. A method for controlling exhaust gases produced by an internal combustion engine comprising: obtaining a vehicle data signal responsive to the engine performance of said internal combustion engine; processing said vehicle data signal so as to formulate an engine operating parameter, wherein said engine operating parameter is responsive to the hydrocarbon content of said exhaust gases; and controlling the fuel introduced into said internal combustion engine in a manner responsive to said engine operating parameter.
 2. The method of claim 1, wherein said obtaining includes communicating said vehicle data signal to an engine control module.
 3. The method of claim 1, wherein said vehicle data signal includes engine speed.
 4. The method of claim 1, wherein said vehicle data signal includes engine torque.
 5. The method of claim 1, wherein said vehicle data signal includes exhaust gas volume.
 6. The method of claim 1, wherein said vehicle data signal includes transmission gear position.
 7. The method of claim 1, wherein said vehicle data signal includes exhaust gas temperature.
 8. The method of claim 1, wherein said engine operating parameter includes fuel injection parameters.
 9. The method of claim 1, wherein said processing said vehicle data signal includes processing said vehicle data signal via an engine control module.
 10. The method of claim 1, wherein said processing said vehicle data signal includes measuring said hydrocarbon content of said exhaust gases.
 11. The method of claim 1, wherein said processing said vehicle data signal include estimating said hydrocarbon content of said exhaust gases.
 12. The method of claim 1, wherein said controlling includes increasing the amount of fuel introduced into said internal combustion engine.
 13. The method of claim 1, wherein said controlling includes decreasing the amount of fuel introduced into said internal combustion engine.
 14. The method of claim 1, wherein said controlling includes maintaining the amount of fuel introduced into said internal combustion engine.
 15. The method of claim 1, wherein said controlling includes introducing fuel into said internal combustion engine at predetermined times responsive to said engine operating parameter.
 16. A medium encoded with a machine-readable computer program code for controlling exhaust gases produced by an internal combustion engine, said medium including instructions for causing controller to implement a method comprising: obtaining a vehicle data signal responsive to the engine performance of said internal combustion engine; processing said vehicle data signal so as to formulate an engine operating parameter, wherein said engine operating parameter is responsive to the hydrocarbon content of said exhaust gases; and controlling the fuel introduced into said internal combustion engine in a manner responsive to said engine operating parameter.
 17. A system for controlling exhaust gases produced by an internal combustion engine comprising: a vehicle sensor for obtaining a vehicle data signal responsive to the engine performance of said internal combustion engine; and an engine control module for processing said vehicle data signal so as to formulate an engine operating parameter, wherein said engine operating parameter is responsive to the hydrocarbon content of said exhaust gases, and wherein said engine control module controls the fuel introduced into said internal combustion engine in a manner responsive to said engine operating parameter. 